This thesis focuses on the study of the northern Iroquoians fortifications from 1400 to 1650 A.D. The Huron, Iroquois and Iroquoians of the St. Lawrence are the main groups under study. The initial objective was to understand the lack of fortification on Saint-Anicet site and to verify some ethnohistorical information suggesting that only the most imposing villages were fortified. Our study, based on 207 sites, confirms that the larger villages were more often fortified, particularly among the Hurons. However, at the Iroquoian level, we denote fortifications on small sites and their absence on some large sites. We also found that Huron, St. Lawrence Iroquoians and Iroquois border sites, near other groups, were more often fortified regardless of their size. In addition, the increase in the number of fortified sites for the three groups coincide with an increase in intra-group and inter-group conflicts. Our study also confirms the close relationship between a prolonged sedentary lifestyle and the presence of a palisade.
From the compiled data, we also observed the evolution of different physical characteristics of the fortifications (number of rows, pile size), related structures (embankment / ditch, entrances, galleries, internal separations), European influence and species of wood used for construction. Again, the increase in pile size and number of rows is consistent with an increase in conflict, while the presence of prehistoric related defensive structures and the use of embankments and ditches among the St. Lawrence Iroquoians confirm a defensive vocation from the XVe century.
Finally, we discuss the symbolic and social integration value of the Iroquoian fortifications. The adequacy of the data concerning the physical evolution of the Iroquoian palisades, as well as their limited symbolic and social integration value, confirms in our opinion the prevalent defensive function of the Iroquoian fortifications from 1400 to 1650 AD. We recognize, however, the social and symbolic implications of fortifications, whose opportunist construction was essentially communal and non-coercive.